1. Field
Example embodiments relate to electric energy generating devices, and for example, to an electric energy generating device including a piezoelectric structure and an insulating film having electret characteristics, and/or a method of driving the same.
2. Description of the Related Art
Research has been conducted into electric energy generating devices that convert various types of energies, including mechanical energy, which are generated in an ordinary living environment, into electrical energies by using piezoelectric nano wires grown on a substrate. Electric energy generating devices may include piezoelectric nano wires on a flat bulk type substrate. However, when such an electric energy generating device is used, it is difficult to efficiently generate electric energy from low intensity energy, e.g., low intensity external vibrations or sound waves, due to the bulk type substrate. Thus, research on electric energy generating devices that generate electric energy from mechanical energy generated, e.g., from a motion of a human body, or vibration energy generated, e.g., from external noise, by using a textile having flexible and stretchable characteristics, e.g., clothing, as a substrate is being done. When an electric energy generating device using a textile substrate is used, a piezoelectric effect may be enhanced and an output voltage generated may be efficiently increased, since the textile substrate has improved conformal coverage and a rough surface, and vibrates sensitively in response to an external environment.